Only a few pages into the whole story, God regrets that He made man in the first place. He's upset with how the earth has turned out, particularly how it had turned away from Him in sin. (Note that He's not upset with how the heavens turned out and only targets the earth with His sorrow.)
Despite His hurt and His bold statement about destroying everything, however, He doesn't. Not really. He saves one righteous man and his family, seven pair of every clean animal, and two pair of every unclean animal, plus enough food to feed them - food that contains the seed of plant life on earth. Which means that when God decides to start over, He still believes in His original design. The earth is just as full at the reboot as it was in the beginning, and life is given the same mandate as before - be fruitful and multiply and fill the earth.
But there is something dramatically, and crucially, different in the way that things start anew after the flood as compared to how they began in the beginning, something that sets the stage for everything we know about being a people of God, being a faithful people of God.
When God started this whole thing, He built a beautiful, lush garden and put man there. In a place teeming with life, teeming with fruit, teeming with shade and shelter and flowing with love. Nourished by the rivers running through it, Eden was the place to be. Man walked with God there, but he did not worship; Adam and Eve never built a single altar in Eden. They didn't have to.
After the flood, God brought the Ark to settle on Mount Ararat - on the mountain. A place with rough terrain, difficult life, where everything flows down instead of through, nourished by the sky above. The mountain is a whole different place to be, a place that reflects more realistically what it is to be bound to the earth for a season. And what's the first thing Noah does when the ship hits the mountain and comes to rest? He worships.
Throughout their history, the people of God have centered their worship on the mountain. This is why. It's because when everything reboots, when everything starts over, when God regrets the earth and begins again and makes a covenant with men, it's on the mountain. It's because when life gets a second chance, it's on the mountain. It's because, all the way back at Noah, ship hit mountain and changed the dynamic of man and God forever.
We talked about this a little at Christmas, when we talked about what it meant to go tell it on the mountain - go tell it to the faithful people of God first. The people of God had their disagreements; they had their differences. One of the biggest ones was which mountain they should be worshiping God on. They weren't arguing over whether they should worship God on the mountain or in the streets. Whether they should set up synagogues next to the river or in lush fields. Anyone and everyone who desired to be faithful to God knew that you worshiped God on the mountain. A mountain.
It's how it was set up, not from the beginning, but from the second beginning, the starting anew. All the way back in Genesis 6. God delivers life to man in the form of a sprig of green in a dove's mouth, places a rainbow in the sky to seal the new covenant, and man builds an altar on the mountain and begins to worship. And that becomes what he does, what he knows, how he lives.